Homework Assignment 4
Due: Tuesday, April 3

• Exercises 3.2: 2. (e), 4.
• Exercises 3.3: 1. (a), (b), 2.
• Exercises 3.4: 5., 6. (b) (iii), (viii), 8. (b)
• Also: A matching is an undirected graph where every vertex has degree one. Thus, a finite matching must have an even number of vertices. Let C be the collection of all finite matchings. Show that there is no sentence in the predicate logic of graphs such that for every M in C, the sentence is true for M if and only if M has an even number of edges. One way to do this is with the Ehrenfeucht game.